I’d say it’s a safe bet that the Herpes virus is best known for its role in ugly, painful sores popping up on your lips, in your mouth and, well, er, other places. However, that doesn’t mean it can’t serve a different purpose. Just a few genetic modifications by researchers at the University of Michigan has the virus stopping pain rather than causing it.
Specifically, I’m talking about the first clinical trial of gene therapy for pain relief recently conducted by David Fink, M.D., Robert Brear Professor and chair of the Department of Neurology, and recently published in the Annals of Neurology.
Gene therapy has been a medical magic bullet long promised and sought ever since the beginning of the Human Genome Project. The problem, of course, is that few traits or diseases are caused by single gene mutations. And the fact that introducing new genes to a person’s body can be dangerous with unpredictable side-effects. That probably has something to do with its failure to become reality too.
But this initial trial went swimmingly.
Ten patients were suffering from unrelenting pain caused by cancer. The pain was so unrelenting that it wasn’t even lessened by 200 mg/day of morphine. Obviously desperate, the patients opted to take part in a trial to relieve their pain.
Researchers took the herpes simplex virus and modified it so that it was incapable of reproducing. (So much for cold sores. Can they do that to mine, please?) But instead of its sore-causing DNA, the virus was loaded with NP2, a gene transfer vector that expresses the naturally-occurring opioid peptide enkephalin.
I’m sure you recognized one of those words – opioid. So yes, NP2 gets one of your body’s natural pain-killing mechanisms rolling on overdrive in the specific locations it is administered. And since that mechanism uses the receptors affected by opioids, you can bet its powerful stuff.
In short, it worked. Plain and clear. Those on a low dose of the gene therapy reported no changes, while those on moderate to high doses reported substantial pain relief. And to make matters better, nobody died or started exhibiting abnormal growths on their eyeballs.
That, my friends, is a science/gene therapy win.